.\" Copyright (c) 2004 Ruslan Ermilov
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice, this list of conditions and the following disclaimer.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice, this list of conditions and the following disclaimer in the
.\"    documentation and/or other materials provided with the distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
.\" ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
.\" SUCH DAMAGE.
.\"
.Dd May 5, 2010
.Dt NG_HUB 4
.Os
.Sh NAME
.Nm ng_hub
.Nd packet distribution netgraph node type
.Sh SYNOPSIS
.In netgraph/ng_hub.h
.Sh DESCRIPTION
The
.Nm hub
node type provides a simple mechanism for distributing packets over
several links.
Packets received on any of the hooks are forwarded out the other hooks.
Packets are not altered in any way.
.Sh HOOKS
A
.Nm hub
node accepts any request to connect, regardless of the hook name,
as long as the name is unique.
.Sh CONTROL MESSAGES
This node type supports the generic control messages, plus the
following:
.Bl -tag -width foo
.It Dv NGM_HUB_SET_PERSISTENT Pq Ic setpersistent
This command sets the persistent flag on the node, and takes no arguments.
.El
.Sh SHUTDOWN
This node shuts down upon receipt of a
.Dv NGM_SHUTDOWN
control message, or when all hooks have been disconnected.
Setting the persistent flag via a
.Dv NGM_HUB_SET_PERSISTENT
control message disables automatic node shutdown when the last hook gets
disconnected.
.Sh SEE ALSO
.Xr netgraph 4 ,
.Xr ng_bridge 4 ,
.Xr ng_ether 4 ,
.Xr ng_one2many 4 ,
.Xr ngctl 8 ,
.Xr nghook 8
.Sh HISTORY
The
.Nm
node type appeared in
.Fx 5.3 .
.Sh AUTHORS
.An Ruslan Ermilov Aq Mt ru@FreeBSD.org
